package com.example.sync.utils;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Hashtable;

/**
 * 生成二维码工具类
 * @author gaofeng
 * @date 2022年08月29日 23:11
 */
public class GenerateQrCodeUtils {

    private static final Integer BLACK = 0xFF000000 ;
    private static final Integer WHITE = 0xFFFFFFFF ;

    public static void getQrCodeImage(String content, File file, String format) {
        Hashtable<EncodeHintType, String> hintType = new Hashtable<>();
        hintType.put(EncodeHintType.CHARACTER_SET, "utf-8") ;
        int width = 300;
        int height = 300 ;
        try {
            BitMatrix matrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hintType) ;
            writeToFile(matrix, format, file);
        } catch (WriterException | IOException e) {
            e.printStackTrace();
        }
    }

    public static BufferedImage toBufferedImage(BitMatrix matrix) {
        int width = matrix.getWidth();
        int height = matrix.getHeight();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_BGR) ;
        for (int i = 0; i < width; i++) {
            for (int j = 0; j < height; j++) {
                image.setRGB(i, j, matrix.get(i, j) ? BLACK : WHITE);
            }
        }
        return image ;
    }

    public static void writeToFile(BitMatrix matrix, String format, File file) throws IOException {
        BufferedImage image = toBufferedImage(matrix);
        if (!ImageIO.write(image, format, file)) {
            throw new IOException("Could not write an image of format " + format + " to " + file);
        }
    }

    public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException {
        BufferedImage image = toBufferedImage(matrix);
        if (!ImageIO.write(image, format, stream)) {
            throw new IOException("Could not write an image of format " + format);
        }
    }
}
